1. Appendages (1) Cutaneous glands – all exocrine glands
Form in stratum basale and push down into dermis
(A) Sebaceous (oil) glands
Everywhere but palms and soles
Most ducts empty into hair follicles
Produce sebum – oily substance and fragmented cells
Keep skin moist
Have chemicals to kill bacteria
Production especially stimulated
by male sex hormones

2. (B) Sweat glands (sudoriferous)
More than 2.5 million
2 types
Eccrine glands
All over
Produce sweat: water, salts, vitamin C, metabolic wastes, lactic acid
Clear
Acidic – pH inhibits bacteria
Opening = pore – directly to surface
Regulate body temp
Stimulated by nerve endings
May lose up to 7 liters on a hot day

3. Apocrine glands
Axillary and genital areas
Ducts open into hair follicles
Secrete fatty acids, proteins, and all of eccrine secretions
Milky/yellowish color
1st stimulated by sex hormones during puberty
Activated by nerve endings

4. (2) Hair/Hair follicles
Hair follicle produces hair
Epidermal sheath – inner
Dermal sheath - outer
Root – hair portion in follicle
Shaft – hair on surface
Medulla – center
Cortex – intermediate
Cuticle - outer
Highly keratinized dead cells
Color caused by melanocytes in bulb
Arrector pilli – smooth muscle – pulls hair upright to add an insulating air layer

5. (3) Nails Scalelike modification of epidermis Keratinized dead cells
Appear pink because of dermal blood supply
Parts
Free edge
Body
Root
Nail folds – overlapping skin
Proximal fold – cuticle
Nail bed – nail matrix – proximal end = nail growth
Lunula – white crescent – over nail matrix

6. Infections & Allergies
Athlete’s foot – tinea pedis
Itchy, red peeling – fungal infection
Boils & carbuncles – inflammations of hair follicles and sebaceous glands

7. Cold sores – fever blisters
Caused by herpes infection
Blisters itch and sting
Activated by stress, fear UV radiation
Contact dermatitis – caused by chemical exposure
Ex. Poison ivy

8. Psoriasis – autoimmune disorder
Impetigo
Caused by staph
Pink, water filled, raised lesions
Develop yellow crust and rupture
Psoriasis – autoimmune disorder
Red lesions covered by dry, silvery scales
Overproduction of skin cells

9. Skin Cancer Benign – does not metastasize (spread)
Malignant – metastasizes
Most common cancer in humans (1 in 5)

10. Types
(1) Basal cell carcinoma
Least malignant – slow growing
Most comon
Stratum basale cells invade dermis
Form small dome shaped lesions w/ a central ulcer
Common on face

11. (2) Squamous cell carcinoma
Stratum spinosum
Scaly, reddened papule (elevation) – shallow ulcer w/ raised border
Rapid growth – metastasizes to lymph nodes
Common on scalp, ears, hands, lower lip

12. (3) Malignant melanoma In melanocytes
5% of skin cancers – 50% chance of survival
Spreading brown/black patch
Metastasizes to lymph nodes and blood vessels

13. ABCD Rule – to recognize melanoma
A – asymmetry
B – border irregularity – not smooth
C – color – does it contain different colors
D – diameter – larger than 6mm

14. Burns Caused by heat, electricity, UV radiation, chemicals Problems:
(1) Allow fluid to seep out (contains proteins and electrolytes)
May lead to kidney shutdown and circulatory shock
Must replace fluids
(2) Infection – leading cause of death w/ burns
Bacteria and fungi may invade

15. Determine extent of burns using “Rule of Nines”
Body is divided into 11 areas (each 9% of body surface) and genital area (1%)
Critical
25% of body w/ 2nd degree
10% w/ 3rd degree
Face/hands/feet w/ 3rd degree
If on face they may cause swelling and suffocation

16. Classified by severity
1st degree – only epidermis
Red, swollen
Heal w/in 2-3 days
Ex. Most sunburns
Aka partial thickness burn

17. 2nd degree – epidermis and upper dermis
Red, blisters
Regeneration can still occur
Aka partial thickness burn

18. 3rd degree – all of epidermis and dermis
Not painful – destroys nerve endings
Gray, white, or blackened
No regeneration
Aka full thickness burn

19. Development Birth Lanugo – downy covering – infant sheds by birth
Vernix caseosa – white substance produced by sebaceous glands
Milia – accumulation
of vernix caseosa in
glands which can be
seen through skin

20. Adolescence
Becomes oily
Acne
20’s – 30’s
Optimal appearance
Old age
Hypodermis thins = cold intolerance
Thinning = easier bruising
Dries out
Hair – loses luster, graying
# follicles decreases = thinning hair
Alopecia - baldness